It's likely you see zeros just because the hit container or the criteria in the segment. For example, maybe an order events happens on the page ABC that is not in the segment, or it gets tracked without a page view call.
When I breakdown those two segments with a segment called Visits from social sites - Only the visit metric is populated with data in the B2B segment. Visits from social sites is built with a visit container.
B2C and B2B segment is built up the exact same way:
HIT HIT Page contains -"- -OR- HIT URL without parameter starts with -"- -OR- URL without parameters start with -"-
The metrics are relevant. For example orders, units and conversion rate.